The 49ers-Seahawks rivalry looms as one of the NFC's juiciest heading into the season, but it was the St. Louis Rams -- not Seattle -- who went undefeated against San Francisco in 2012.
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Following a 24-24 tie with the 49ers in Week 10, the Rams knocked off Jim Harbaugh's bunch 16-13 in overtime just three weeks later. Former Rams safety Craig Dahl, now a 49er, says there's a reason for that.
"We had a few tips off film we were able to differentiate between run and pass early," Dahl said Wednesday, per Cam Inman of Bay Area News Group. "So that kind of gave us an added benefit on defense."
Said Dahl: "Different personnel and different alignment stuff really were the big keys as far as giveaways. It's been addressed and corrected. They knew most of it before I even got here. We just reconfirmed it. It's ongoing self-study and self-scouting that got it cleared up, too."
That happens in football, but it's surprising from the 49ers, considering offensive coordinator Greg Roman is among the NFL's most creative play-callers. San Francisco hit defenses with a frenzy of alignments and looks last season.
As Matt Maiocco of Comcast SportsNet Bay Area points out, preventing a repeat of this falls partly on newly hired offensive consultant Eric Mangini, who was brought on to help the team self-scout its tendencies.
UPDATE:Rams cornerback Cortland Finneganoffered a warning to his former teammate Wednesday, via Twitter.
"Craig Dahl we know how you play thanks for the tips," Finnegan wrote, "we know who to attack early and often."
Follow Marc Sessler on Twitter @MarcSesslerNFL.